integer(random(256)); will give you a number from 0 to 256, random(256); will give you a number from 0.001 to 256.000

the structure you use if up to you and how you can work with best, the only thing you have to be careful of is that things are DEFINED BEFORE THEY ARE USED.

for example:

function add(i)
{
a = a+i;
}

var a = 0;

is bad

var a = 0;

function add(i)
{
a = a+i;
}

is good